It's simply that it's the least bad system that humanity can come up with.
A benefic dictator is the least bad system that humanity can come up with.
"dictator" doesn't seem compatible with the outcome I'm after: freedom. Perhaps we can quibble over what effect him being benefic would have to make dictatorship compatible with freedom. I'd be fine then.
Unfortunately, there have been less of these people in the entire history of Earth than I have fingers on my left hand, so democracy wins on practicality.
I think that was, in essence, my point. Democracy is the least bad (perhaps I should have added "practical") system.
Thankfully we don't have real democracy. That's just a recipe for disaster unless you have the democratically-elected equivalent of a benefic dictator. Without such a strong leader, pure democracy devolves into weasels promising anything and everything in order to gain power.
Actually, with real democracy, I don't suppose there would be any such thing as a "leader". Every decision would be decided by the majority (not that I think that would be a good thing, as minorities would tend to get screwed). What we mostly have (in the west) are representative democracies. We give our power (expressed with a vote) to a few, whom we select according to their stated policies and our judgement of their character.
We seem to be getting by using that system I suppose; but I wouldn't say that I find myself singing its praises.